Luminaire



Jan. 13, 1942. T w ROLPH 2269,554-

LUMINAIRE -Filed March l, 1938 2 Sheets-Sheet l INVENTOR Thomas W Rolph BY ATTO RN EY Tlc'l. I I ,5 i

'Jan' 13, 1942- T. w. RoLPH 2,269-,554

I LUMINAIRE Filed March l, 1938 2 SheetS-Sheet 2 ATTORNEY -up the light in that rectangular area.

Patented Jan. 13, 194 2 Thomas W. ltolph, Newark, Ohio, assignor tof Holophane'Company, Inc., New York, N. Y., a.

corporation of Delaware Application March 1, 1938, seriaiNo.193,248

(C1. zie-7.35)

,f ,4 oiaims.

The present invention relates to luminaires and is more particularly directed toward llminaires designed for the lighting of Vrailway' cars, street cars, busses and other vehicles and the like wherein seats are arranged in'fixed posi-.

tions relative to the car area.

In such Vehicles the seating arrangement is practically always one such that the fioor area of the vehicle may be' considered to be dvided into a number of identical Vor substantially identical rectanguiar areas. Such rectangular areas may include the Vportion of the car onV opposite sides of the aisle whichis normally. occupied by two pairs of double seats arranged one in front of the other (usually having eight seating areas) or may include the half of this area on one side of the aisle or the two seating areas of a single double seat'. Where the largerarea is to obtainits principal lighting from a single' lighting unit, the unit Iis 'placed near the ceiling over the aisle and according to the present invention the lighting unit has light concentrating prisms whichbuild Where areas above the seat or seats. on one side of the aisle are to he lighted, the units are arranged over the seats and disposed so vas to provide rectangular light distributions of appropriate size. These units may beoffsetted relative to the center' of the area and the beam directed in an oblique direction to cover the area. The various arrangements of lighting unitsV contemplated by the present invention make it possible to place on the reading areas a satisfactory light intensity without glare, and sufiicient spilled light is obtained from the units in a vehicle to light the non-reading areas, side walls and aisles.

The accompanying drawings show, for purposes of illustratng the present invention, several embodiments in which the invention may are illustrative of the invention rather than limiting the same.

In these drawings:

Figures 1, 2 and 3 are top plan, longitudinal, and transverse sectional views through one form of luminaire for car lighting, Figure 2 being taken on a broken line 2-2 of Figure 1, and Figure 3 being taken on the broken line 3-3 of Figure l, parts being broken away to show interior construction;

Figures 4, 5 and 6 are top plan, longitudinal, and transverse sectional views through another form of luminaire for car lighting, Figure 5 be'- ing taken on the line 5-5 of Figure 4, and Figure 6 being taken on the line 5-5 of Figure 5 and Figure 7 is a 'lon'gitudinal sectional view through 'a further modified forr of onstrpction. p In the arrang'ement vs'hown in/Egures 1, 2 and 3, the refractor is made up of two pieces 30and 3|, of prismatic light transmitting material. In plan view the refractor is rectangular. It nas an i arcuate cross-section in transverse planes so as tobe cylindrical as shown in Figure 3. Theup- 'i per surfaceof the lower or outer element 30 of the refractor is provided with 'longitudinally extending light 'concentrating prisms 32. These light concentrating prisms as shown in Figure 3, are arranged symmetrical with respect to two oblique Vaxes through the light source LC so as to 'concentrate the light as indicated by the light The refractors 30 and 3i are nested as indicated and held in registry by fianges 3|a .on the inner refractor which overlie the edges of the outer refractor 30. Thelatter has flanges 30a to facilitate mounting the refractors in a suitable frame. I

This form of'luminaire is particularly adapted for useover the' ca'f aisleand when mounted in this position, the .refractor is placed so that light is concentratedl into two beams which span the aisle and fall on the opposite pairs of seats.

To obtain ceiling illumination, the end walls of the inner refracting element are provided with light elevating. prisms indicated at 36 and the opposed walls of the outer refracting element are provided with diffusing flutes indicated at 31. i

In the arrangement shown in Figures 4, 5, and 6, the refractor 40 has a flat bottom 4| and side and end walls 42 and 43. The lower surface of .take form, it being understood that the drawings 40 the bottoin4l of the refractor is provided with longitudinallyl extending light concentrating prisms 44, while vthe upper surface of the bottom of the refractor is provided with two sets of transversely extending light concentrating prisms 45 and 46. The prisms, 45 form a lens system for a-light source-indicated at 41 while the prisms 46 form alens system for a light source indicated at 48. These light sources are in the plane of the axis of the lower set of prisms and each is oifsetted from the axial planeof the corresponding set of upper prisms so that the beams of light are tilted as indicated by the light rays 49 and 50.

The arrangement shown in Figures 4, 5 and 6 is designed for mounting` over the double seat in II may be provided with diflusing flutes II and I I'he refractor 80 shownin Fig. "l, is substantially the same as the refractor shown in Figures 4, and 6, except that the upper surface of the bottom of the refractor is provided with a single lens system 6| adapted to co-operate with the light source located at 62. The paths of light rays are indicated at 63.

It is obvious that the invention may be embodied in many forms and constructions within the scope of the claims and I wish it to be understood that the particular forms shown are but a few of the many forms. Various modifications and changes being possible, I do not otherwise limit myself in any way with respect thereio.

I claim: i

l. A car lighting luminaire adapted for ilush mounting in the ceiling of the car and comprising a light source,`a refractor comprising two nested refractor parts, the inner part having peripheral fianges to fi't the edges of the outer part and provide a rectangular opening .to receive light from the source, the parts having substantially` Vertical opposed end walls of substantial depth and protruding below the ceiling so as to he in the line of vision of seated occupants of the car, at least one of the walls including vertical light diifusing fiutes for laterally spreading light for ceiling illumination and obscuring' the source, the bottomof one refractor part having a series of light concentrating prisms parallel with two opposite side edges of the refractor part. the bottom of the other refractor part having a series of light concentrating prisms opposed to the first series of prisms and at right angles thereto, the light source being in the focal line of the set of prisms parallel with the length of the rectangle to spread an intense beam over a rectangular area below-the luminaire, the refractor parts being of arcuate cross section in vertical planes across the width of the rectangle.

2. A car lighting luminaire adapted for ilush mounting in the ceilingof the car and comprising a light source, a'refractor comprising two nested refractorparts'L the inner part having peripheral iianges 'tofit the, edges of the outer part and provide' 'a"`rectangular opening to receive light from'the source, the parts having substantially ve'rtical opposed end walls of substantial depth and protrudlng below the ceiling so as to be in the line of vision of seated occupants of the car,

at least oneof the walls including Vertical light diffusing nutes for laterally spreading light for ceiling illumination and obscuring the source, the bottom lof one'refractor part having a series of light eoncentrating prisms parallel with two opposfte side edgesv of the refractor part, the bottom of the other refractor part having a series of light concentrating prisms opPOsed to the first series of prisms and at right angles thereto, the light source being in the focal line of the set of prisms parallel with the length of the rectangle to spread an intense beam over a reotangular area below the luminaire, the refractor parts being semi-cylindrioal and the longitudinal extending prisms concentrating the light into two oblique beams.

3. A car lighting luminaire adapted for fiush mounting in the ceiling of the car and comprising a light source, a refractor comprising two nested refractor parts, the inner part having peripheral fianges to fit the edges of the outer part and provide a rectangular opening to receive light from the source, the parts having substantially vertical opposed end walls `vof substantial depth and protruding below the ceiling so as to be in the line of vision of seated occupants of the car. at least one of 'the walls including Vertical light diffusing flutes for laterally spreading light for ceiling illumination and obscuring the source, the bottom of one refractor part having a series of light coneentrating prisms parallel with two opposiie side edges of the refractor part, the bottom of the other refractor part having a series of light concentrating' prisms opposed to the first series of prisms and atright angles thereto, the light source being in the focai linev of the set of prisms parallel with the length of the rectangle to spread an intense. beam over a rectangular area below the luminaire, the refractor parts being semi-cylindrical and the Vertical endwalls on one part being vprovided with light elevating prisms.

4. A car lighting luminaire comprising a flat bottomed rectangular shaped refractor having in the lower surface of the bottom longitudinally extendlng light concentrating prisms and on the upper surface of the bottom two sets of transversely disposed light concentrating prisms, and a light source disposed over each set of transverse prisms and in the axial plane of the lower set of prisms.

THOMAS W. ROLPH. 

